The concept of refuse disposal in solution-mined salt cavities was introduced by Z. W. Rogers Jr. in a paper entitled "Process for Refuse Disposal in Solution-Mined Salt Cavities" delivered to the Fourth International Symposium on Salt--Northern Ohio Geological Society in 1968. The proposed process involved the steps of conveying refuse through a reclamation and shredding facility, and then dropping the refuse down a large diameter disposal shaft extending from the groundsurface to the top of the salt cavity. A small diameter shaft was to be provided for ventilating the cavity during disposal operations. The internal pressure of the cavity was preferably atmospheric to allow the introduction of refuse into the cavity in the most direct manner possible.
In his paper Rogers also discussed what he termed "alternate disposal techniques". Two alternate techniques were discussed under this heading, one being the production of a water based slurry from the refuse and the other being pressurizing the cavity. He viewed the slurry approach as being the more "inefficient" method as there would be no "compaction due to refuse overburden". He also noted that the extraction of brine to accommodate the addition of refuse slurry would present problems of possible plugging. He suggested that a method of addressing there apparent problems would be to extract the brine from within a gravel packed sump at the base of the cavity and then running the brine through a settling pond or centrifuge.
The teachings of Rogers have been successfully applied with contaminated soil such as drill cuttings produced by the oil industry. The contaminated soils are mixed into a slurry with a salt water brine and then injected into a salt cavity. This technique has been successful due to the fact that contaminated soil has a specific gravity per cubic foot which exceeds that of the brine. The heavier contaminated soil component settles to the bottom of the salt cavity permitting the brine to be drawn away from the top of the cavity and recycled.
The problems envisaged by Rogers with respect to the slurry method still serve as an impediment from applying these techniques to municipal refuse. Municipal refuse is not a homogeneous product, as is contaminated soil. A large proportion of municipal refuse consists of matter, such as wood and paper, that has a specific gravity of less than brine. Matter with a specific gravity of less than brine will not settle to the bottom of the cavity, and as such creates serious problems with brine circulation.